There are a number of different blood tests that tell us about hepatitis B virus infection.

The test result you mention, the surface antigen (often abbreviated sAg), typically tells us that there is chronic hepatitis B virus infection. This means on ongoing, persistent infection in the liver. If the sAg is positive, it is helpful to be evaluated by a doctor over time; hepatitis B can change over time in someone's body.

A helpful next blood test is the hepatitis B DNA. The DNA test result can determine whether the hepatitis B virus is currently replicating in your liver cells (making new viruses every day). This result can help your doctor determine if you should take medications to treat this infection.

With chronic hepatitis B infection, it is important to quit smoking if you smoke, and to cut down and ideally not use any alcohol.

If you have not had an HIV test recently, I suggest that you talk with your doctor about an HIV test. The presence of both viruses is an indication to take medications for both viruses. There are effective, safe medications available to treat hepatitis B, and HIV.

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